Senile dementia has been greatly concerned in a society where many advanced aged persons live, and different efforts have been made of the prevention and therapy for the disease. Particularly, a senile dementia referred to as Alzheimer disease often shows symptoms in the presenile (50 to 60 years), so it is desired to elucidate causes of the disease and to establish the therapy for it.
The obtained findings up to date suggest that Alzheimer disease is an organic disease which has pathological characteristics such as senile blemish and neurotic fiber degeneration, and a clinical characteristic of progressive dementia, and which is involved in enhanced metabolism and abnormal regeneration of neuron.
However, effectively preventive and therapeutic methods for Alzheimer disease have not been found, thereby establishment of them is desired.